A major problem which exits with swimming pools, both commercial and residential, is keeping such pools clean. Dust, dirt and other foreign matter enters the water and settles on the bottom. In addition, leaves, bugs, feathers and the like accumulate on the water and ultimately become saturated and sink to the bottom. Modern swimming pools all employ recirculating pump systems for withdrawing water from drains located at the bottom and from skimmers located at the water surface. This water then passes through a filter which removes suspended particles from the water prior to returning the water to the pool after it has been filtered. Water circulation pumps for achieving this purpose operate for extended periods of times, in some cases continuously, throughout the life of the pool. In some systems, chemicals, such as chlorine, are injected into the return water for the pool, either prior to or after filtering of the water has been effected.
Systems have been developed for causing "automatic" cleaning of pools. The newest and most effective automatic pool cleaning systems use pop-up cleaning heads in the floor and the walls of the pool to eject water under high pressure in relatively narrow streams adjacent the pool surface to stir up any dirt and small particles which otherwise would settle to the bottom or stick to the walls of the pool. This material is placed in suspension where it is withdrawn through the drain and skimmer for circulation through the filter described above. Such automatic in-floor pool cleaning systems, have reached a very sophisticated state and are extremely effective in maintaining pool cleanliness with one primary exception.
In-floor pool cleaning systems inherently do not have a capability of handling leaves and the like. As a result, the conventional leaf skimmer continues to be a necessary part of any pool system. Leaf skimmers typically are located in a well or cavity adjacent the pool and have an inlet which is partially submerged and partially above the normal water level for the pool. The inlet has a one way pivoted floating dam in it to permit water and leaves to pass into the leaf skimmer, but the dam prevents leaves and other surface debris from passing out of the skimmer into the pool. To cause surface water to move from the pool into the skimmer, the recirculation pump normally withdraws at least a portion of the water for recirculation and filtering from the bottom of the skimmer in addition to water withdrawn from the drain in the bottom of the pool. Consequently, the water which flows through the recirculating pump is pulled through the skimmer and the skimmer leaf basket on a continuous basis.
As leaves and other debris are pulled into the leaf basket, they tend to plug up the openings in the basket and restrict the water flow through it. It is necessary to periodically empty the leaf basket to prevent substantial restriction of the water flow through it. If the leaf basket is not emptied, it is possible to completely or significantly block water flow through the basket to the recirculating pump, causing the recirculation operation to be impaired. If all of the return water were to be withdrawn through a conventional leaf skimmer, it would be possible to restrict the water flow to such an extent that damage to the pump could exist. For that reason, most pool systems cause the water withdrawn from the pool by the pump to be pulled both from the leaf skimmer and from the drain at the bottom of the pool.
It is desirable to provide a leaf skimmer which has all of the advantages of conventional leaf skimmers, but which does not interfere in any way with the recirculating water flow through the pump and filter system. Furthermore, it is desirable to provide such a leaf skimmer at little or no additional cost over conventional leaf skimmers currently employed with swimming pools.